Publish to a LinkedIn company Page
post_to_linkedin_pagePublish a post to one of the user’s LinkedIn COMPANY PAGES — text, plus optionally an image, a video, a 2–20 image CAROUSEL (LinkedIn calls it a MultiImage post; pass the slides in order as imageUrls[]), or a LINK POST with a real preview card (linkUrl). USE linkUrl WHENEVER THE POINT OF THE POST IS A LINK: LinkedIn disables URL scraping for API partners, so a url sitting in the text renders as plain text with no card, and the card’s title, description and image only exist if you pass linkTitle / linkDescription / linkThumbnailUrl — read them off the page and supply them. The media need not be a Hermoso render — it must be Hermoso-HOSTED because we upload the bytes to LinkedIn ourselves, and upload_file turns ANY file the user already has into such a URL. ORGANIC CAROUSELS ARE COMPANY-PAGE ONLY — a personal profile cannot publish one and is refused by name, so send a deck here rather than to post_to_linkedin. This is a DIFFERENT thing from post_to_linkedin, which publishes to the person’s own profile: pick the one the user actually asked for and never substitute. organizationId comes from list_linkedin_pages; omit it only when the account administers exactly one Page. This PUBLISHES immediately and PUBLICLY — ALWAYS show the user the exact text and get an explicit yes BEFORE calling. A VIDEO POST CAN CARRY CAPTIONS AND ITS OWN COVER, and both are attached only during the upload: pass captionsSrt (SubRip content — LinkedIn is watched with the sound off) and videoThumbnailUrl (otherwise LinkedIn picks a frame for you). LinkedIn does NOT allow the image, video, captions or thumbnail of a published post to be swapped afterwards, so get all of that right first (the copy can still be edited with manage_linkedin_post).
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| hook | No | WHAT ANGLE THIS POST IS BUILT ON — the single most valuable field here, and the only moment it can ever be recorded. post_performance groups on it to answer "which hooks work", and it needs 5 posts sharing ONE hook before it will call anything a winner, so REUSE THE SAME WORDING across a campaign instead of rephrasing it every time. Best of all, pass a hook id from list_hooks (e.g. "direct_callout", "mid_problem", "before_after") — those fold onto a stable key however they are spelled, so a whole brand accumulates evidence on one row. Your own wording is fine too; it just only groups when you repeat it exactly. Omitting it means this post can never vote on which hook works. | |
| text | Yes | the post text | |
| title | No | video title | |
| altText | No | accessibility alt text (max 4086 characters, ~120 recommended). A STRING describes every image; an ARRAY describes each slide of a multi-image post separately, in slide order — LinkedIn stores altText per image, and their own sample request carries a different one on each. Not available on a PERSONAL-profile post: LinkedIn’s member posting API has no alt-text field at all. | |
| linkUrl | No | publish a LINK POST — LinkedIn renders a real preview card for this URL instead of leaving a bare link in the text. Mutually exclusive with imageUrl / videoUrl / imageUrls: LinkedIn’s content field is a union, so combining them is refused by name rather than one being dropped. | |
| subject | No | WHAT THIS POST IS ABOUT — the product, feature, offer or theme (e.g. "winter coat", "free trial", "founder story"). The second grouping axis in post_performance. Same rule as hook: reuse the exact wording so posts about one subject land in one group. | |
| imageUrl | No | a Hermoso-hosted image URL — a render (list_library), or ANY image of the user’s own passed through upload_file first. An arbitrary external host is refused. | |
| videoUrl | No | a Hermoso-hosted video URL — a render, or the user’s own footage via upload_file. LinkedIn processes it before publishing, which takes a minute. | |
| imageUrls | No | CAROUSEL — an ORDERED list of image (and, where the channel allows, video) URLs published as ONE post the viewer swipes through. THIS IS NOT “post several” — it is a single post with several slides, which is what a multi-slide creative (a listicle, a “1/6 · SWIPE” deck) actually needs; publishing only its first slide tells the viewer to swipe at something that cannot. The ORDER is the product. Limits per channel: Instagram 2–10 (images, videos or a mix), Threads 2–20 (mix allowed), Facebook 2+ (Meta publishes no documented maximum; Hermoso caps the upload fan-out at 30 and says so), LinkedIn company Pages 2–20 (images only), Pinterest 2–5 (images only), TikTok up to 35. One url here is simply an ordinary single post. Anything a channel cannot do is REFUSED with the real reason — nothing is ever quietly downgraded to one slide. | |
| linkTitle | No | the headline ON the preview card. LINKEDIN NEVER SCRAPES THE PAGE — their Posts API disables URL scraping for API partners outright — so if you do not pass this the card renders UNLABELLED. Fetch the page’s own title and pass it. | |
| visibility | No | default PUBLIC | |
| captionsSrt | No | CLOSED CAPTIONS for a videoUrl post — the SubRip (.srt) CONTENT itself, cue numbers and `00:00:00,000 --> 00:00:02,000` timing lines included, NOT a URL and NOT the plain script (a file with no timings is refused, because LinkedIn would accept it and then silently never show it). Most of LinkedIn is watched with the sound off, so an uncaptioned video is one most of the feed never hears. LinkedIn allows ONE caption file per video and ENGLISH ONLY; it can be attached only WHILE the video is uploaded, never added to a published post; and it is processed asynchronously, so the reply confirms it was UPLOADED and never that it is visible yet. Requires videoUrl — passing it on an image, carousel or link post is refused by name. | |
| allowDuplicate | No | post it even though an identical post was just made or attempted. Only pass this when the user genuinely wants the same thing posted twice, or when you have LOOKED at the account and confirmed a timed-out attempt did not land. | |
| idempotencyKey | No | SAFE RETRIES. Publishing can take minutes (a video upload, a carousel of ten slides) and a transport can time out while the post SUCCEEDS — retrying blind is how the same thing gets posted twice. Pass any stable string here and a repeat of the SAME publish returns the ORIGINAL post id instead of posting again (24h). You do not have to: an identical publish is auto-recognised for 10 minutes anyway. If a call times out or errors ambiguously, CALL AGAIN WITH THE SAME KEY — that is the safe move, and it will either report the original post or publish it for the first time. It never posts twice. | |
| organizationId | No | numeric Page id from list_linkedin_pages | |
| linkDescription | No | the sub-line on the preview card. Same rule as linkTitle: absent means blank, because LinkedIn will not fetch it. | |
| linkThumbnailUrl | No | a Hermoso-hosted image used as the card’s picture (uploaded to LinkedIn for you). Without it the card has no image. | |
| videoThumbnailUrl | No | the COVER IMAGE for a videoUrl post — a Hermoso-hosted image (a render, or any picture of the user’s via upload_file). Without it LinkedIn adds a system-generated thumbnail, which on an ad is usually whatever the first frame happens to be. Like captions this can only be set WHILE the video is uploaded, never afterwards. Requires videoUrl. This is NOT linkThumbnailUrl, which is the picture on a link-preview card. |